Wolff-Parkinson White

Wolff-Parkinson White (WPW) syndrome is caused by a congenital accessory conducting pathway between the atria and ventricles leading to atrioventricular re-entry tachycardia (AVRT). As the accessory pathway does not slow conduction AF can degenerate rapidly to VF.

Image sourced from Wikipedia

Possible ECG features include:

• short PR interval
• wide QRS complexes with a slurred upstroke - 'delta wave'
• left axis deviation if right-sided accessory pathway
  • in the majority of cases, or in a question without qualification, Wolff-Parkinson-White syndrome is associated with left axis deviation
• right axis deviation if left-sided accessory pathway

Differentiating between type A and type B

• type A (left-sided pathway): dominant R wave in V1
• type B (right-sided pathway): no dominant R wave in V1

Associations of WPW

• HOCM
• mitral valve prolapse